THERAPEUTIC APPROACH OF COMPLICATED HYDATID DISEASE: ROLE OF ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY IN CHOLANGIOHYDATIDOSIS

ABSTRACT BACKGROUND: Hydatid disease, a parasitic infestation caused by Echinococcus granulosus larvae, is an infectious disease endemic in different areas, such as India, Australia, and South America. The liver is well known as the organ most commonly affected by hydatid disease and may present a wide variety of complications such as hepatothoracic hydatid transit, cyst superinfection, intra-abdominal dissemination, and communication of the biliary cyst with extravasation of parasitic material into the bile duct, also called cholangiohydatidosis. Humans are considered an intermediate host, exposed to these larvae by hand-to-mouth contamination of the feces of infected dogs. AIM: This study aimed to highlight the role of endoscopic retrograde cholangiopancreatography in patients with acute cholangitis secondary to cholangiohydatidosis. METHODS: Considering the imaging findings in a 36-year-old female patient with computed tomography and magnetic resonance imaging showing a complex cystic lesion in liver segment VI, with multiple internal vesicles and a wall defect cyst that communicates with the intrahepatic biliary tree, endoscopic biliary drainage was performed by endoscopic retrograde cholangiopancreatography with papillotomy, leading to the discharge of multiple obstructive cysts and hydatid sand from the main bile duct. RESULTS: Clinical and laboratory findings improved after drainage, with hospital discharge under oral antiparasitic treatment before complete surgical resection of the hepatic hydatid cyst. CONCLUSIONS: Endoscopic retrograde cholangiopancreatography is a safe and useful method for the treatment of biliary complications of hepatic hydatid disease and should be considered the first-line procedure for biliary drainage in cases of cholangiohydatid disease involving secondary acute cholangitis.


Central Message
The liver is well-known as the most common organ affected by hydatid disease, which may present a wide variety of complications such as hepatothoracic hydatid transit, cyst superinfection, intra-abdominal dissemination, and biliary cyst communication with parasitic material leak into the bile duct, also called cholangiohydatidosis. hepatic hydatid cyst resection. Written informed consent was obtained from the patient for publication of this case and any accompanying images (CEC-01 Servicio de Salud del Maule Scientific Ethics Committee nº 61606900-4).

DISCUSSION
Hepatic hydatidosis is a complex zoonotic disease that remains a major worldwide health problem, especially in endemic INTRODUCTION H ydatid disease, a parasitic infestation caused by the larvae of Echinococcus granulosus, is an endemic infectious disease in different areas, such as India, Australia, and South America 8,16 . The human is considered an intermediated host, exposed to these larvae by hand-to-mouth contamination from stool from infected dogs 16 . The liver is wellknown as the most common organ affected by hydatid disease, which may present a wide variety of complications such as hepatothoracic hydatid transit, cyst superinfection, intra-abdominal dissemination, and biliary cyst communication with parasitic material leak into the bile duct, also called cholangiohydatidosis 3,14 . The migration of parasitic elements into the bile ducts throughout the cystic communication may generate a biliary obstructive syndrome with secondary acute cholangitis 7 . Although there are different biliary drainage techniques, endoscopic retrograde cholangiopancreatography (ERCP) is actually considered the first-line drainage procedure in biliary obstruction syndrome, mainly due to its high effectiveness and lower risk of adverse events 4,6,9 . In this article, we aim to highlight the role of ERCP in patients with acute cholangitis secondary to cholangiohydatidosis.

Case Report
A 36-year-old woman with a medical history of bronchial asthma presented to our hospital with the complaints of generalized and diffuse upper abdominal pain, fever, and progressive jaundice of 2-day duration. On hospital admission, she was mild febrile and tachycardic. Initial evaluation revealed a total bilirubin concentration (2.78 μmol/L), elevated white blood cell count (WBC) (10.980/mm 3 ), and C-reactive protein (CRP) (118 μmol/L). Alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, platelet count, and prothrombin time were normal. After the severity assessment, general supportive care was immediately started, with clinical improvement after completing antimicrobial therapy.
In view of her favorable clinical response, computed tomography (CT) and magnetic resonance imaging (MRI) were obtained, depicting a complex cystic lesion in the VI hepatic segment, with multiple inner vesicles (Figure 1), and a cystic wall defect that communicates to the intrahepatic biliary tree (Figure 2), associated with an intrahepatic and extrahepatic bile duct dilatation ( Figure 3).
Considering the imaging findings, endoscopic biliary drainage by ERCP with papillotomy was performed, leading to the discharge of multiple obstructive daughter cysts and hydatid sand from the main biliary tract (Figure 4). Both clinical and laboratory findings improved after drainage, with the patient being discharged home under oral antiparasitic treatment prior to its complete surgical    countries, with an estimated annual incidence of above 50 cases per 100,000 people 1 . At present, a wide variety of complications have been described 12 . However, the cystic communication to the bile duct with parasitic material migration into the biliary tree represents a life-threatening condition that can lead to mild-to-severe acute cholangitis, secondary pancreatitis, sepsis, and death 3 . Clinically, these patients present symptoms of biliary obstruction syndrome, while laboratory findings are nonspecific 7 . Imaging findings (abdominal ultrasound, CT, or MRI) can depict a communication between a cystic wall and biliary radicles, with the existence of pus and linear structures passing through the defect and filling the bile tract 12 . According to the initial severity assessment, general supportive care and early intravenous antimicrobial therapy are key elements in the first-line therapy of cholangiohydatidosis, especially among those cases that involve bile duct infection and secondary biliary sepsis 11 . The biliary tract drainage is considered the main treatment, which can be performed by endoscopic management, conventional surgery, or percutaneous transhepatic biliary drainage (PTBD) 10 . Compelling evidence supports that ERCP is the procedure of choice for biliary decompression and drainage for biliary obstruction, including uncommon causes such as cholangiohydatidosis 7,4,11,15 . Despite the risk of post-ERCP complications, which ranges between 0.5 and 5% 2 , clinical evidence shows that ERCP drainage has both high success rates (80-100%) 5,13 and lower adverse outcomes such as bile leakage, inflammation, pain, and impairment of the patient's quality of life, compared to PTBD and conventional surgery 7,4,13,15 .